A flower algorithm for autonomous star identification in space surveillance

Abstract

The recent increase of space threats yields the idea of using the existing star trackers to perform surveillance of space objects from space. In the missions, due to the observer attitude dynamics, smearing affects the observed stars on the image in space surveillance. Besides, the reflecting flying space objects or debris as spurious stars affects the attitude determination. These are devastating for most star identification algorithms in star trackers. To resolve the problems, this paper defines a star pattern, called Flower code, which is composed of angular distances and circular angles as the characteristics of the pivot star. The angular distances are used for initial lookup table match. Moreover, the circular angles are used for the cyclic dynamic match between the sensor pattern and the pattern candidates from the initial match. The focus of the results is the evaluation of the influence of the reflecting flying spacecraft or debris as spurious stars and the attitude dynamics of the observer spacecraft, on the performance of the algorithms. A number of experiments are carried out on simulated images. The results demonstrated that the proposed method is efficient and robust.